Interleukin 6-174G>C polymorphism and risk of aneurysmal subarachnoid hemorrhage: case-control study and meta-analysis

Abstract

Vascular inflammation contributes to the pathogenesis of aneurysmal subarachnoid hemorrhage (aSAH). Interleukin 6 (IL6) is a proinflammatory cytokine involved in many vascular pathologies. Two studies analyzing an association of the functional IL6 gene -174G>C promoter polymorphism with aSAH provided inconsistent results. The aim of this study was to investigate whether this IL6 polymorphism is associated with aSAH in a Polish population. We genotyped 276 aSAH patients and 581 unrelated control subjects. All were of Caucasian origin. In addition, a meta-analysis combining results of the current and previously published studies was conducted. The distribution of IL6 genotypes and alleles did not differ significantly between aSAH (GG - 29.7%, GC - 50.0%, CC - 20.2%, G - 54.7%) and control subjects (GG - 32.0%, GC - 47.3%, CC - 20.7%, G - 44.3%). In the meta-analysis, the IL6-174G>C polymorphism was not associated with aSAH risk either. We failed to find an association between the IL6 -174G>C polymorphism and aSAH in analyzed European populations.